even if they share the same excact chassis, the manufacturer (nissan,toyata,etc) still has to make a formal statement saying that the chassis will react the same in a crash as it's us counterpart. Which no JDM auto maker has ever done so far. Without the manufactuer's statement you have to crash multiple cars, and spend a great deal of money to make it possible for anyone to legalize them. Which is what was done with the 2-door 32-34 skylines.
Just keep in mind, just because you see people driving around true jdm cars, doesn't mean that they're legal. And with a front clip it's pretty easy to make an unsafe rhd jdm wanna be, car, so you can tell people it's jdm tyte.
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